VACCINE

The Science Of The Total Environment • September 2011
Mercury exposure and risks
from dental amalgam in the US population
post-2000
Author information
Richardson GM1, Wilson R,
Allard D, Purtill C, Douma S, Gravière J.
SNC-Lavalin Environment, Suite 110
20 Colonnade Road, Ottawa, ON Canada
mark.richardson@snclavalin.com
Abstract
Dental amalgam is 50% metallic mercury (Hg) by weight and Hg vapour continuously
evolves from in-place dental amalgam, causing increased Hg content
with increasing amalgam load in urine, faeces, exhaled breath, saliva, blood, and
various organs and tissues including the kidney, pituitary gland, liver, and brain.
The Hg content also increases with maternal amalgam load in amniotic fluid, placenta,
cord blood, meconium, various foetal tissues including liver, kidney and
brain, in colostrum and breast milk. Based on 2001 to 2004 population statistics,
181.1 million Americans carry a grand total of 1.46 billion restored teeth. Children
as young as 26 months were recorded as having restored teeth. Past dental
practice and recently available data indicate that the majority of these restorations
are composed of dental amalgam. Employing recent US population-based
statistics on body weight and the frequency of dentally restored tooth surfaces,
and recent research on the incremental increase in urinary Hg concentration per
amalgam-filled tooth surface, estimates of Hg exposure from amalgam fillings
were determined for 5 age groups of the US population. Three specific exposure
scenarios were considered, each scenario incrementally reducing the number of
tooth surfaces assumed to be restored with amalgam. Based on the least conservative
of the scenarios evaluated, it was estimated that some 67.2 million
Americans would exceed the Hg dose associated with the reference exposure
level (REL) of 0.3 μg/m(3) established by the US Environmental Protection
Agency; and 122.3 million Americans would exceed the dose associated with
the REL of 0.03 μg/m(3) established by the California Environmental Protection
Agency. Exposure estimates are consistent with previous estimates presented
by Health Canada in 1995, and amount to 0.2 to 0.4 μg/day per amalgam-filled
tooth surface, or 0.5 to 1 μg/day/amalgam-filled tooth, depending on age and
other factors.
“Based on the least conservative of the
scenarios evaluated, it was estimated that
some 67.2 million Americans would exceed
the mercury dose associated with the reference
exposure level (REL) of 0.3 μg/m(3) established
by the US Environmental Protection Agency;
and 122.3 million Americans would exceed
the dose associated with the REL of 0.03 μg/m(3)
established by the California Environmental
Protection Agency.”
http://www.ncbi.nlm.nih.gov/pubmed/?term=21782213